1. Field of the Invention
The invention relates generally to enclosures and, more particularly, to door hinge assemblies for electrical enclosures. The invention also relates to electrical enclosures employing door hinge assemblies.
2. Background Information
Electrical equipment such as, for example, relays, circuit breakers, electric meters and transformers, are typically housed within an enclosure such as, for example, a housing, such as a box or cabinet, to protect the electrical equipment. When such electrical equipment is disposed outdoors, it must be protected from the environment, for example, to prevent electrical faults caused by moisture. Accordingly, outdoor electrical enclosures are provided with a variety of moisture-resistant devices such as hoods and/or overlapping covers, and adjustable doors.
FIG. 1 shows an example of one such enclosure. Specifically, an outdoor electrical enclosure 2 is shown which generally comprises a housing 4 having opposing sides 6,8, a back panel 10 extending between the sides 6,8, a bottom 12, a hood 14, and a door 16. The door 16 is coupled to side 6 of the housing 4 by way of a pair of telescopic hinge assemblies 18. The telescopic hinge assemblies 18 are structured to permit the door 16 to be adjusted in the vertical direction for providing a proper moisture-resistant fit with respect to the hood 14, such that the hood 14 partially covers or overlays the top of the door 16 when the door 16 is closed. Telescopic hinges are discussed, for example, in U.S. Pat. No. 6,879,483 issued on Apr. 12, 2005 to Johnson et al., entitled “Outdoor Electrical Enclosure and Hood Therefor.” Each telescopic hinge assembly 18 includes a hinge pin 20, which is coupled to the side 6 of the enclosure housing 4, and a corresponding hinge bracket 22. The hinge brackets 22 are separate components which are suitably fastened to the side flange 24 of the door 16, typically by welding (e.g., spot welding). Each hinge bracket 22 includes a curled tubular portion 26 structured to pivotably receive a corresponding one of the hinge pins 20, and a flange 28 which is welded to the door side flange 24. Similar multi-component hinge assemblies (not shown) are employed for pivotable doors (not shown) which are not required to be telescopic in nature, with the primary difference of such doors being only that the pins (not shown) are not structured to provide vertical movement of the door 16.
Such multi-component hinge assemblies (e.g., 18) suffer from a number of unique disadvantages which are, in large part, related to the nature of their construction. Specifically, properly aligning the separate hinge brackets 22, which are welded to the side flange 24 of the door 16, requires the use of locating protrusions or nibs 30 on the flange 28 which are received in corresponding locating holes (not shown) on the side flange 24. This structure and associated assembly process is cost-intensive and time-consuming. Additionally, the weld process is subject to human error, and can lend to problems having a negative impact on part quality and accuracy. For example, the weld area can be easily contaminated, compromising the integrity of the weld, and weld spatter can enter the curled tubular portions 26 of the hinge brackets 22 thus inhibiting its interaction with the hinge pins 20. Additionally, despite the aforementioned locating nibs 30 and holes (not shown), slight errors in alignment can occur and impede proper function of the hinge assembly 18 and door 16.
Another problem with known electrical enclosures is that the door can come open when it is desired that the door remain closed. For example, in outdoor applications, it is desirable to consistently maintain the door in a closed position in order to avoid the undesired entry of moisture and/or debris. Wind can undesirably open the door and, in some mounting configurations, for example, where the surface or structure to which the enclosure is mounted is not straight and level, the uneven mounting arrangement of the enclosure can cause the door to undesirably open.
Accordingly, there is room for improvement in electrical enclosures, and in door hinge assemblies therefor.